1. Field of the Invention
The present invention relates to a video data processing apparatus, and more particularly, to such apparatus adapted to perform video data compression.
2. Description of the Prior Art
Conventionally, for storing a variety of video data such as a video signal representative of an image and so on in a memory, a video signal formed, for example, by scanning one picture image in line sequence is converted directly to a digital signal which is then stored.
However, the amount of data to be stored should be as small as possible. Consequently, it is necessary to compress the amount of video data derived form the scanned image and store the compressed video data in a memory. There have been proposed a variety of compressing methods which nevertheless need a relatively large scaled circuit arrangement for the data compression. Another drawback associated with these conventional methods is that they provide a relatively small compression ratio for attending to video data in many different conditions. Therefore, such conventional methods are not appropriate to compress, for example, data of images having a relatively strong area correlation (images which exhibit relatively few changes in one image) which may be inputted by hand writing.